铜锰铝合金的高温塑性变形行为研究

Research on High Temperature Pyroplastic Deformation Behavior of Cu-Mn-Al Alloy

通过高温拉伸和热模拟压缩试验,研究了铜锰铝合金的高温塑性变形行为。结果表明:在350℃以下,合金有较好的热稳定性,抗拉强度达860 MPa以上,但伸长率几乎为零;当温度提高至400℃后,合金强度开始降低,伸长率显著增加,材料的韧脆转变温度为365.84℃。在较高应变速率或较低温度时,试验合金的真应力-应变曲线发生“颤振”现象;在较低应变速率(0.001s-1)和较高温度(650℃)时,材料发生显著软化;在500~600℃,合金的流变应力和应变速率满足幂指数关系。

The pyroplastic deformation behavior of Cu-Mn-Al alloy was investigated by high temperature tensile test and thermal simulation compression test.The results show that the alloy has good thermal stability below 350℃,the tensile strength reaches above 860 MPa,but the elongation is near to zero.Then,the strength begins to decrease and the elongation increases significantly after increasing to 400℃,and the ductile-brittle transition temperature of the material is about 365.84℃.In hot simulation compressive process,the"flutter"phenomenon occurs in the true stress-strain curves of the alloy at higher strain rate or lower temperature,the material softens significantly at lower strain rate(0.001 s-1)and higher temperature(650℃).In the range of 500-600℃,the relationship between flow stress and strain rate of the alloy accords with the power exponential law.